CHRISTMAS is great, but there's a little Scrooge in all of us. What makes me feel bah-humbuggy is gifts of no practical use. They fall into three categories: First, gifts from grandparents or other relatives who haven't noticed you're not a kid any more. Things you may have wanted when you were seven, like huge stuffed animals, but that you'd rather run over with your car now because they're so cute. This must be what is meant by "growing up."

Second, gifts you can't figure out. The example classique is the digital watch. I own one with four push-buttons, but never wear it. It came with brain-damaged instructions that I couldn't figure out. An electrical engineer at Cal Tech once set it for me, but when I moved to the East Coast it again became worthless. I've been three hours behind ever since.

Third are the presents you wt to like, but personal integrity intervenes. These often involve clothes. My mother, a woman of impeccable taste, ssof "Timber!" ever closer. One year, a drive to the hardware store yielded an enormous slice of plywood, soon to hold a peaceful little village -- imperiled by a Mount St. Helens flow of pine needles. (If it got too bad, the villagers could catch the train.)

That was the year of the red-and-green tree stand that looked like a dog's dish on four legs. To prop all four legs against the tree trunk, just so, was as impossible as solving a Rubik's cube -- which, by the way, makes a quaint ornament.

Another Christmas brought experiments in the two-nail theory of tree stability. 1. Drive two nails into the wall behind the tree, tie a string to one nail, run it in front of the tree and tie it to the other nail. After 15 minutes, do not stand in front of the tree. 2. For a tree displayed in a window, drive two nails into the window frame, etc., and, after 20 minutes, do not stand in front of the window.

Eventually we learn, and I became the proud owner of a sturdy metal reservoir the size of a small child's swimming pool, with clamps that screw into the trunk.

Last year some friends who for religious reasons do not have a tree came over to help trim ours. Not everyone is a Druid.

Everyone likes trimming trees. We even strung together popcorn garlands.

Two days later, an unexplained arboreal frisson undid their efforts. I redecorated the tree alone.

That was when I began to analyze the tree, turning it so that the natural curvature of the spine (they all have it) bent back toward the wall. That was the year I filled the metal reservoir with bricks for ballast.

Maybe this will be the year we make it through the holidays. Ah well, some listen for sleighbells, while others harken to a tinkling, creaking, whooshing sound in the living room.